Examine source code of amzvar - Price Viewer of Amazon Variation

{
  "name": "amzvar - Price Viewer of Amazon Variation",
  "short_name": "amzvar",
  "version": "0.3.5resigned1",
  "manifest_version": 2,
  "description": "Shown on Amazon product page to provide the lowest price including price history of product variations or recommendations.",
  "homepage_url": "https://shopecific.com/amzvar.html",
  "icons": {
    "16": "icons/amz2_logo_16.png",
    "48": "icons/amz2_logo_48.png",
    "128": "icons/amz2_logo_128.png"
  },
  "default_locale": "en",
  "background": {
    "scripts": [
      "src/bg/background.js"
    ]
  },
  "permissions": [
    "https://www.amazon.com/*",
    "storage"
  ],
  "content_scripts": [
    {
      "matches": [
        "https://*.amazon.com/*"
      ],
      "js": [
        "js/jquery/jquery.min.js",
        "js/jquery/jquery-ui.min.js",
        "src/inject/inject.js"
      ],
      "run_at": "document_start"
    }
  ],
  "web_accessible_resources": [
    "src/inject/inject.css",
    "icons/*"
  ],
  "browser_action": {
    "default_icon": "icons/amz2_logo_48.png",
    "default_popup": "src/options_custom/popup.html"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{84111797-b44b-4bfe-9376-ce755c7530fb}"
    }
  }
}